Anti-uv non-fading fabric based on long afterglow light conversion of rare earth aluminates

Abstract

The application discloses a kind of long afterglow light conversion anti-ultraviolet non-fading fabric based on rare earth aluminate, the fabric includes surface coating modified rare earth aluminate luminescent particles, ultraviolet absorber, hindered amine light stabilizer and the functional coating of coloring microcapsule compound, and with the primer layer comprising nano filler and forms double-layer structure;The application is through luminescent particle coating modification, ultraviolet absorber and luminescent material synergic compounding, colorant microencapsulation and double-layer coating design, so that the fabric afterglow retention rate is ≥75% after 50 times washing, UPF is ≥50+, color difference ΔE is ≤2, realize the effect of anti-ultraviolet, long afterglow and non-fading.

Description

Technical Field

[0001] This invention relates to the field of UV-resistant and colorfast fabric technology, and more particularly to UV-resistant and colorfast fabrics based on the long afterglow light conversion of rare earth aluminates. Background Technology

[0002] Currently, fabrics with UV protection are typically produced by adding UV absorbers or shielding agents during the finishing process. Fabrics with long-afterglow luminescence properties are often produced by coating or printing sulfide or aluminate long-afterglow materials onto the fabric surface. Rare earth aluminate long-afterglow materials have become one of the main choices for preparing luminescent fabrics due to their high afterglow brightness, long duration, and relatively good chemical stability.

[0003] Conventional UV absorbers in anti-UV finishing agents absorb or block some UV light, while the excitation of long-afterglow materials requires the absorption of UV light to store energy. When both coexist in the same coating system, competitive absorption easily occurs, leading to a significant decrease in the initial brightness and duration of the afterglow. Furthermore, rare-earth aluminate long-afterglow materials are prone to hydrolysis during washing, especially in weakly acidic or weakly alkaline media, where their crystal structure is damaged, resulting in rapid decay of luminescent performance. Simultaneously, traditional organic pigments or dyes undergo photofading under long-term UV irradiation, and the visible light continuously emitted after excitation by long-afterglow materials may also cause photobleaching or photochromism affecting the color stability of certain colorants, resulting in uneven color or overall color fading of the fabric during use. Additionally, the cross-linking system used to improve the bonding strength between the coating and fibers, if having poor interfacial compatibility with the surface of the long-afterglow particles, is prone to developing microcracks after repeated friction or bending, further accelerating the shedding of luminescent particles and performance degradation.

[0004] Therefore, in response to the problems mentioned above, this invention proposes an anti-UV and colorfast fabric based on the long afterglow light conversion of rare earth aluminates. Summary of the Invention

[0005] To overcome the problems of mutual inhibition between long-afterglow luminescence and UV protection in existing technologies, rapid decay of luminescence performance after washing, and easy fading of fabrics, this invention proposes a UV-resistant and colorfast fabric based on the long-afterglow light conversion of rare-earth aluminates. This fabric constructs a specific functional coating structure, using surface-modified rare-earth aluminate luminescent particles combined with UV absorbers, hindered amine light stabilizers, and nano-UV-resistant particles, along with appropriate binders and crosslinking systems. While achieving highly efficient UV shielding, it converts some UV light into long-afterglow visible light, thereby avoiding competitive absorption. At the same time, through the stabilization design of the colorant within the coating, it achieves the effect of being washable and colorfast.

[0006] The technical solution of this invention is: an anti-UV and colorfast fabric based on rare-earth aluminate long afterglow light conversion, the fabric comprising: The base fabric layer is a blend of polyester and cotton fibers in a blend ratio of 50:50 to 80:20, and undergoes plasma pretreatment or alkali reduction treatment. This base fabric layer is manufactured using woven, knitted, or nonwoven processes, and has a basis weight of 80-300 g / m². 2 ; A functional coating is laminated on the upper surface of the base fabric layer. The functional coating has a two-layer structure, including a base coating that is in direct contact with the base fabric layer and a top coating that covers the base coating. The base coating is a polyurethane resin layer containing a crosslinking agent, with a thickness of 5-30 μm. The base coating also contains 1-5% nano-silica or nano-alumina by weight of the total mass of the base coating to improve the hardness and scratch resistance of the base coating. The surface coating is a light conversion functional layer with a thickness of 30-100 μm, and the surface coating contains the following components in parts by weight: (1) 30-70 parts of rare earth aluminate long afterglow luminescent material particles, the chemical composition of which is as follows: ,in The doping concentration is 0.5-5 mol%. The doping amount is 1-10 mol%; the average particle size of the luminescent material particles is 0.5-20 μm, and each particle surface is covered with a dense silica protective layer with a thickness of 20-80 nm. Hydrophobic or hydrophilic groups are grafted onto the outside of the protective layer through a silane coupling agent, wherein the silane coupling agent is γ-aminopropyltriethoxysilane or γ-methacryloyloxypropyltrimethoxysilane. (2) 0.5-10 parts of ultraviolet light absorber, selected from at least one of benzotriazoles, triazines, benzophenones or cyanoacrylates, preferably 2-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole; (3) 0.5-8 parts of hindered amine light stabilizer, selected from at least one of piperidine, piperazine or imidazole hindered amine compounds, preferably bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate; (4) 20-60 parts of adhesive, selected from at least one of waterborne polyurethane, waterborne acrylate, waterborne epoxy resin or silicone resin; (5) 1-15 parts of nano-anti-ultraviolet particles, wherein the nano-anti-ultraviolet particles are rutile titanium dioxide, zinc oxide or cerium oxide, with an average particle size of 10-100 nm, preferably rutile titanium dioxide with an average particle size of 20-50 nm, and the surface is modified by stearic acid or silane coupling agent. (6) 0.5-5 parts of crosslinking agent, selected from at least one of aziridine, carbodiimide, isocyanate or epoxysilane; (7) 0.2-3 parts of dispersant, selected from at least one of polycarboxylate, polyacrylate or polyether-modified siloxane; (8) 1-20 parts of colorant, wherein the colorant is an active dye, a vat dye or a nano pigment, preferably a nano pigment, wherein the nano pigment is coated in polyacrylate microspheres by in-situ polymerization to form colored microcapsules, and the average particle size of the colored microcapsules is 0.5-5 μm; (9) Thickener 0.1-2 parts, leveling agent 0.1-1 parts; the thickener is selected from at least one of polyurethane associative thickener, acrylate copolymer thickener or sodium carboxymethyl cellulose; the leveling agent is selected from at least one of polyether modified polysiloxane, polyacrylate leveling agent or perfluoropolyether; After the fabric is irradiated with 200-400nm ultraviolet light for 10 minutes, the initial afterglow brightness when the irradiation is stopped is not less than 300mcd / m². 2 The afterglow decayed to 0.32 mcd / m 2 The time should not be less than 6 hours; After 50 washes according to AATCC61-2010 standard, the fabric retains an initial brightness of ≥75%, and compared with before washing, the color difference ΔE≤2, light fastness ≥4, and rubbing fastness ≥4. The fabric has an ultraviolet protection factor (UPF) of ≥50+ and a UVA transmittance of ≤5%; The beneficial effects of this invention are: 1. This invention modifies rare earth aluminate long afterglow luminescent material particles by coating them with silica and grafting them with silane coupling agents, so that the afterglow brightness retention rate of the fabric can still reach more than 79.5% after 50 washes, and the acid / alkali hydrolysis resistance retention rate exceeds 74%, which significantly overcomes the problem of easy hydrolysis failure of traditional aluminate luminescent materials.

[0007] 2. This invention combines an ultraviolet light absorber and a hindered amine light stabilizer with a rare earth aluminate luminescent material in the same coating. By utilizing light modulation and free radical capture mechanisms, it achieves synergistic enhancement of anti-ultraviolet and long afterglow, thus breaking the problem of competitive absorption between the two.

[0008] 3. This invention uses nano-organic pigments to encapsulate polyacrylate microspheres through in-situ polymerization to form colored microcapsules, resulting in a color difference ΔE≤2 after 50 washes and a light fastness of grade 4 or higher, effectively solving the problem of easy fading of long-afterglow luminescent fabrics under ultraviolet and visible light irradiation. Attached Figure Description

[0009] Figure 1 The diagram shown is a structural schematic of the present invention; Figure 2 The diagram shown illustrates the preparation process of this invention.

[0010] Explanation of reference numerals in the attached diagram: 1. Base fabric layer; 2. Primer layer; 3. Topcoat layer. Detailed Implementation

[0011] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0012] Please see Figure 1 and Figure 2 The present invention provides Embodiment 1: This example uses a blended yarn of polyester and cotton fibers at a ratio of 65:35, and produces a plain weave fabric with a base fabric weight of 180 g / m². 2 After undergoing conventional pretreatments such as desizing, scouring, and bleaching, the obtained fabric surface is pretreated with low-temperature oxygen plasma using a plasma surface treatment device. The treatment power is 300W and the treatment time is 90 seconds, thereby improving the adhesion between the subsequent coating and the base fabric.

[0013] According to chemical formula middle The doping concentration is 2.5 mol%. A doping concentration of 5 mol% was determined by weighing out high-purity strontium oxide (SrO2). ), aluminum oxide ( europium oxide ) and dysprosium oxide ( Add an appropriate amount of boric acid ( As a flux, after being ball-milled and mixed evenly, it is then applied in a reducing atmosphere (95%). +5% The luminescent material particles were reacted at 1350℃ for 3 hours, then naturally cooled, pulverized, and sieved to obtain luminescent material particles with an average particle size of 8 μm. 100 g of the luminescent particles were dispersed in 500 mL of ethanol, and 15 g of tetraethyl orthosilicate and 10 mL of ammonia (25%) were added. The mixture was stirred at 40℃ for 4 hours, then heated to 80℃ and reacted for another 2 hours. After centrifugation, the particles were washed three times with ethanol and dried at 100℃ for 12 hours to obtain luminescent particles with a dense silica layer on the surface. Transmission electron microscopy showed that the silica layer thickness was approximately 45 nm. 100 g of the coated luminescent particles were dispersed in 500 mL of toluene, and 5 g of γ-aminopropyltriethoxysilane was added. The mixture was refluxed and stirred at 80℃ for 6 hours under nitrogen protection, centrifuged, washed with toluene, and dried under vacuum at 60℃ to obtain modified rare-earth aluminate long-afterglow luminescent material particles with surface-grafted amino hydrophobic groups.

[0014] The topcoat slurry is prepared according to the following parts by weight: 50 parts modified luminescent material particles, 5 parts ultraviolet light absorber 2-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole, 3 parts hindered amine light stabilizer bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate, 45 parts waterborne polyurethane binder (solid content 40%), 8 parts nano rutile titanium dioxide (average particle size 35nm, surface modified with stearic acid), 2 parts aziridine crosslinking agent, 1 part sodium polycarboxylate dispersant, 12 parts colored microcapsules, 0.8 parts polyurethane associative thickener, 0.4 parts polyether modified polysiloxane leveling agent, and deionized water to make up to a total solid content of 45%.

[0015] The preparation method of the colored microcapsules is as follows: 5g of red nano-organic pigment is mixed with 10g of methyl methacrylate monomer, 0.2g of azobisisobutyronitrile initiator, and 0.5g of sodium dodecyl sulfate emulsifier, and dispersed in 100mL of deionized water under a high-speed emulsifier to form a fine emulsion. The mixture is then heated to 75℃ and polymerized for 6 hours to obtain polyacrylate-coated pigment microcapsules with an average particle size of 2.5μm. The above components are then added sequentially to a mixing tank, stirred at a low speed of 300rpm for 10 minutes, and then dispersed at a high speed of 1200rpm for 30 minutes. After filtration and degassing, a topcoat slurry is obtained.

[0016] The primer coating slurry is prepared separately: 100 parts of waterborne polyurethane resin (35% solid content), 3 parts of aziridine crosslinking agent, 2 parts of nano silica (average particle size 20nm), 0.5 parts of polyurethane associative thickener, and deionized water to adjust the viscosity to 2000mPa·s (25℃). Stir well and set aside.

[0017] The primer coating slurry is evenly applied to the upper surface of the base fabric using a roller coating method, with a coating amount of 15 g / m². 2The substrate is pre-baked at 80℃ for 2 minutes, then dried at 120℃ for 3 minutes to form a base coating with a thickness of approximately 12μm. A topcoat slurry is then applied over the base coating using a doctor blade coating method, with a coating weight of 80g / m². 2 The coating is dried at 80°C for 5 minutes and then cured at 150°C for 3 minutes to form a surface coating with a thickness of about 65μm, thus obtaining the final fabric product.

[0018] This invention provides Embodiment 2: The difference between this example and Example 1 is that the base fabric layer uses a blend of polyester fiber and cotton fiber in a ratio of 70:30, and the base fabric weight is 150 g / m². 2 Furthermore, the pretreatment of the base fabric adopted alkali reduction treatment instead of plasma treatment: the blank was placed in an 8 g / L sodium hydroxide solution, treated at 85°C for 30 minutes, and then thoroughly washed, neutralized, and dried. The thickness of the base coating was adjusted to 10 μm, and the thickness of the top coating was adjusted to 55 μm. The weight parts of each component in the top coating were adjusted as follows: 45 parts of modified luminescent material particles, 6 parts of ultraviolet light absorber, 4 parts of hindered amine light stabilizer, 48 parts of waterborne polyurethane binder, 10 parts of nano-rutile titanium dioxide, 3 parts of aziridine crosslinking agent, 1.5 parts of sodium polycarboxylate dispersant, 10 parts of coloring microcapsules, 1.2 parts of thickener, and 0.6 parts of leveling agent, thus obtaining the sample of Example 2.

[0019] This invention provides embodiment 3: The difference between this example and Example 1 is as follows: the UV absorber in the topcoat is replaced with a triazine (2,4,6-tris(2-hydroxy-4-hexyloxy-3-methylphenyl)-1,3,5-triazine), and the nano-anti-UV particles are replaced with zinc oxide (average particle size 30 nm, surface modified with the coupling agent γ-methacryloxypropyltrimethoxysilane). The silica coating thickness of the luminescent material particles is 60 nm, and the graft coupling agent is γ-methacryloxypropyltrimethoxysilane. The weight parts of each component in the topcoat are adjusted as follows: 55 parts modified luminescent material particles, 4 parts UV absorber, 2.5 parts hindered amine light stabilizer, 42 parts waterborne polyurethane binder, 6 parts nano-rutile titanium dioxide, 1.5 parts aziridine crosslinking agent, 0.8 parts sodium polycarboxylate dispersant, 15 parts colored microcapsules, 1.0 part thickener, and 0.5 parts leveling agent. The nano-silica in the base coating was replaced with nano-alumina, and the amount added was 3% of the total mass of the base coating, resulting in the sample of Example 3.

[0020] Comparative Example 1 provided by the present invention: The luminescent material particles in Comparative Example 1 were used directly without silica coating or silane coupling agent grafting modification, and were not surface-treated. The particles (average particle size 8 μm) were the same as those in Example 1, and the other raw materials and processes were the same.

[0021] This experiment compares Examples 1, 2, and 3 with Comparative Example 1. Specifically: (1) Perform 50 water washes according to AATCC 61-2010 standard and test the retention rate of the initial brightness of the afterglow before and after the water wash.

[0022] (2) The samples were immersed in an acetic acid buffer solution with pH=5.5 and a sodium carbonate buffer solution with pH=8.5 respectively, and soaked at 40°C for 72 hours. After being taken out, they were thoroughly washed with water and dried, and the retention rate of the initial brightness of the afterglow was tested.

[0023] (3) Under the conditions of 365nm ultraviolet light and 1000lx, irradiate for 10 minutes and test the initial afterglow brightness and afterglow duration of each sample in the unwashed state.

[0024] (4) Coating adhesion cross-cut test (GB / T 9286-2021) and observation of coating condition after 5000 abrasion cycles.

[0025] The results are shown in Tables 1 and 2: Table 1. Effect of surface coating on long-afterglow luminescence and water-wash resistance.

[0026] Table 2. Effects of surface coating on hydrolytic stability and coating durability.

[0027] As shown in Table 1, the initial afterglow brightness of Examples 1-3 was higher than that of Comparative Example 1, and the afterglow duration was also longer. This is because the silica coating on the surface has anti-reflection and interface optimization effects, reducing non-radiative transition centers on the particle surface and improving the utilization efficiency of excitation energy. Furthermore, after 50 water washes, the brightness retention rate of Examples 1-3 all reached over 79.5%, while that of Comparative Example 1 was only 52.3%. This indicates that the uncoated bare particles underwent lattice hydrolysis during the water washing process due to water penetration, resulting in the dissolution of Sr and Al ions and the loss of luminescent centers. Oxidation causes a sharp decline in performance.

[0028] Table 2 shows that after soaking in acidic (pH=5.5) and alkaline (pH=8.5) environments for 72 hours, the afterglow retention rates of Examples 1-3 remained above 77% and 74%, respectively, while the retention rates of Comparative Example 1 were less than 49% and 44%, respectively. This indicates that the dense silica layer effectively blocked the afterglow. and The erosion of the aluminate lattice significantly improved the hydrolytic stability of the luminescent material. Simultaneously, the introduction of hydrophobic or hydrophilic groups onto the coated particle surface via silane coupling agent grafting improved compatibility with the waterborne polyurethane adhesive, ensuring the coating remained intact after abrasion testing. All samples showed a cross-cut adhesion rating of 0, indicating that the coating modification did not reduce the bond between the coating and the base fabric; rather, the improved interfacial compatibility enhanced the overall cohesive strength of the coating.

[0029] Comparative Example 2 is provided in this invention: In Comparative Example 2, no UV absorber or hindered amine light stabilizer was added to the topcoat, and the remaining raw materials and processes were the same as in Example 1.

[0030] This experiment compares Examples 1, 2, and 3 with Comparative Example 2. Specifically: (1) Measure the initial afterglow brightness, afterglow duration and brightness retention rate after 50 water washes.

[0031] (2) Test the UPF value and UVA transmittance of each case.

[0032] (3) Light fastness test.

[0033] (4) The transmission spectra of the coatings of Comparative Example 2 and Example 1 were tested respectively, and the absorption contribution of the luminescent material to ultraviolet light was calculated.

[0034] Table 3. Effects of UV absorbers / light stabilizers on luminescence and UV protection properties.

[0035] Table 4. Effects of UV absorbers / light stabilizers on light fastness.

[0036] As shown in Table 3, Comparative Example 2, due to the lack of ultraviolet light absorbers and light stabilizers, had an initial afterglow brightness of only 198 mcd / m². 2 The brightness of the light-emitting material is less than half that of Example 1, and the afterglow duration is only 3.2 hours, far lower than the 7.9 hours or more of Example 1. Without the addition of an ultraviolet absorber, the luminescent material directly exposed to high-intensity ultraviolet irradiation will experience over-excitation on its surface, leading to quenching of the excited state concentration. Simultaneously, high-energy photons in the ultraviolet light may induce lattice defect proliferation, reducing luminous efficiency. The addition of the ultraviolet absorber acts as a light modulator, absorbing strong ultraviolet light and transmitting it in a lower energy form or scattering it uniformly, thus providing the luminescent material with more suitable excitation conditions and improving the efficiency of light energy storage and release. At the same time, the hindered amine light stabilizer can capture free radicals generated in the coating due to ultraviolet radiation, preventing photo-oxidative degradation of the luminescent material and the binder, thereby resulting in higher brightness retention after washing.

[0037] Comparative Example 2 had a UPF value of only 38 and a UVA transmittance of 8.7%, failing to meet the national standard requirement of UPF ≥ 50+ and UVA transmittance ≤ 5%; while Examples 1-3 all met the standard. This indicates that although the luminescent material itself has a certain UV shielding capability, it is insufficient to reach an excellent level and must be combined with a UV absorber to achieve highly efficient UV protection. Spectral analysis shows that the average absorbance of the coating in Example 1 in the 280-380nm wavelength range is about 35% higher than that of Comparative Example 2, proving that the two produce a synergistic absorption effect.

[0038] As shown in Table 4, the light fastness of Comparative Example 2 is grade 3, while that of Examples 1-3 reaches grade 4-5. This is because the UV absorber and light stabilizer also protect the colorant and reduce light fading.

[0039] Comparative Example 3 is provided in this invention: In Comparative Example 3, the colorant was not made using coloring microcapsules, but rather by directly adding an equal mass of unencapsulated red nano-organic pigment. All other raw materials and processes were the same as in Example 1.

[0040] This experiment compares Examples 1, 2, and 3 with Comparative Example 3. Specifically: (1) Measure the color fastness to washing, color fastness to dry rubbing and color fastness to wet rubbing.

[0041] (2) Detect the color difference ΔE before and after 50 water washes.

[0042] (3) Test light fastness.

[0043] (4) Observe the pigment distribution on the coating surface after 50 water washes using a scanning electron microscope.

[0044] (5) To test the migration of the colorant in the coating, first, the coating surface is attached to a white cotton cloth and placed at 40°C and 80% relative humidity for 72 hours. Then, observe whether the white cotton cloth is stained.

[0045] Table 5. Effects of microencapsulation on color fastness and color difference.

[0046] Table 6. Effects of microencapsulation on light fastness and migration.

[0047] As shown in Table 5, the color difference ΔE of Examples 1-3 after 50 washes is ≤1.5, while that of Comparative Example 3 is as high as 3.1, with obvious color change visible to the naked eye. Meanwhile, the color fastness to washing of the Examples reaches grade 4-5, while that of Comparative Example 3 is only grade 3. The color fastness to wet rubbing of the Examples is grade 4-5, while that of Comparative Example 3 is only grade 2-3. This indicates that unencapsulated nano-organic pigments have poor compatibility with the polyurethane matrix in the coating, and are prone to precipitation or aggregation with water migration during washing. Furthermore, the pigment particles are directly exposed on the surface and easily detach during rubbing. However, after microencapsulation, the pigments are encapsulated by a polyacrylate shell, which has good compatibility with the water-based polyurethane binder. The pigments are firmly anchored inside the capsules, making them less prone to migration or detachment during washing and rubbing.

[0048] As shown in Table 6, the white cloth in Comparative Example 3 showed significant staining under humid and hot conditions, while Examples 1-3 showed no staining. The lightfastness of Comparative Example 3 was only grade 2-3, far lower than the grade 4-5 of the Examples. This is because exposed organic pigments directly absorb ultraviolet light and visible light emitted by luminescent materials, undergoing photochemical reactions that lead to fading. In contrast, the polyacrylate shell of the microcapsules provides ultraviolet shielding and light filtering, while physically isolating the pigments from external light radiation, significantly improving lightfastness. Scanning electron microscopy observation of the coating surface after water washing revealed that the microcapsules in the Example samples remained uniformly distributed and unbroken, while the pigment particles in the Comparative Example 3 samples showed significant agglomeration, with voids appearing in some areas.

[0049] This invention provides Comparative Example 4: Comparative Example 4 did not apply a base coating; instead, the top coating was applied directly onto the base fabric layer. All other raw materials and processes were the same as in Example 1.

[0050] This experiment compares Examples 1, 2, and 3 with Comparative Example 4. Specifically: (1) Conduct a cross-cut adhesion test on the coating.

[0051] (2) Use the Martindale method to test the wear resistance. The pressure is 12 kPa and the friction is 5000 times. Observe the peeling of the coating and evaluate the grade. Grade 1 is the worst and Grade 5 is the best.

[0052] (3) The initial brightness retention rate of afterglow and the coating weight loss rate after 50 water washes were calculated by weighing method to determine the coating peeling ratio.

[0053] (4) Changes in UV resistance (UPF, UVA transmittance) before and after washing.

[0054] (5) The protective effect of the base coating on the base fabric is evaluated by analyzing the changes in the chemical structure of carbonyl groups, ester groups and other chemical structures in the coating before and after water washing using infrared spectroscopy.

[0055] Table 7. Effects of double-layer coating structure on adhesion, abrasion resistance, and washability.

[0056] Table 8. Effects of double-layer coating structure on UV resistance and water wash stability.

[0057] As shown in Table 7, Comparative Example 4, lacking a base coating, had its top coating directly in contact with the polyester / cotton blended base fabric, resulting in a cross-cut adhesion rating of level 2, while Examples 1-3 all achieved level 0. After 5000 abrasion cycles, the coating edges of Comparative Example 4 showed significant peeling, even exposing the base fabric, while the examples only exhibited slight abrasion marks and no peeling. After 50 washes, the afterglow retention rate of Comparative Example 4 was only 68.9%, with a coating weight loss rate as high as 11.5%, indicating that a large amount of luminescent material was lost as the coating peeled off; while the afterglow retention rates of the examples were all ≥79.8%, and the weight loss rate was ≤3.8%. This demonstrates that the base coating acts as an interfacial coupling layer. The polyurethane and cross-linking agent in the base coating can penetrate into the fiber surface and interior, forming mechanical interlocking and chemical bonding. The addition of nano-silica or alumina further increases the hardness and surface roughness of the base coating, providing a more robust anchoring point for the top coating. Conversely, without a base coat, the binder in the top coat is difficult to fully bond with the hydrophobic polyester fibers, and water molecules penetrate along the interface during washing, causing the coating to peel off in sheets.

[0058] As shown in Table 8, after 50 washes, the UPF value of Examples 1-3 decreased by only 3-4 units, and the UVA transmittance increased by no more than 0.9 percentage points, still meeting the requirement of UPF≥50+. In Comparative Example 4, the UPF decreased from 50 to 38, and the UVA transmittance increased from 5.1% to 8.2%, failing to meet the standard. This indicates that coating peeling led to thinning of the functional layer and deterioration of UV resistance.

[0059] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments that can be applied to other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A UV-resistant, colorfast fabric based on rare-earth aluminate long afterglow light conversion, characterized in that, include: The base fabric layer is made of at least one of polyester fiber, polyamide fiber, cotton fiber, or viscose fiber by weaving, knitting, or nonwoven processes, and the basis weight of the base fabric layer is 80-300 g / m². 2 ; A functional coating is laminated onto the upper surface of the base fabric layer. The functional coating has a single-layer or multi-layer structure, and its total dry film thickness is 20-150μm. The functional coating comprises the following components in parts by weight: 30-70 parts rare earth aluminate long afterglow luminescent material particles, 0.5-10 parts ultraviolet light absorber, 0.5-8 parts hindered amine light stabilizer, 20-60 parts binder, 1-15 parts nano-anti-ultraviolet particles, 0.5-5 parts crosslinking agent, 0.2-3 parts dispersant, 1-20 parts colorant, 0.1-2 parts thickener, and 0.1-1 parts leveling agent; The general chemical formula of the luminescent material particles is: Where M is Ca and / or Ba, 0 ≤ m ≤ 0.3, 0.005 ≤ n ≤ 0.1, and the luminescent material is co-doped with or The molar ratio of co-doped ions to Eu is 0.5-2:

1. The average particle size of the luminescent material particles is 0.5-20 μm, and each particle surface is coated with a protective layer of silicon dioxide, aluminum oxide or titanium dioxide with a thickness of 5-200 nm. Hydrophobic or hydrophilic groups are grafted onto the outside of the protective layer through a silane coupling agent. The ultraviolet absorber, 0.5-10 parts, is selected from at least one of benzotriazoles, triazines, benzophenones, or cyanoacrylates; The hindered amine light stabilizer is selected from at least one of piperidine-based, piperazine-based, or imidazole-based hindered amine compounds; The adhesive is selected from at least one of waterborne polyurethane, waterborne acrylate, waterborne epoxy resin or silicone resin; The nano-anti-UV particles are rutile titanium dioxide, zinc oxide or cerium oxide, with an average particle size of 10-100 nm. The crosslinking agent is selected from at least one of aziridine, carbodiimide, isocyanate, or epoxysilane; The dispersant is selected from at least one of polycarboxylate, polyacrylate, or polyether-modified siloxane; The colorant is a reactive dye, a vat dye, or a nano pigment, and the colorant is fixed in the functional coating by chemical cross-linking or physical encapsulation. After the fabric is irradiated with 200-400nm ultraviolet light for 10 minutes, the initial afterglow brightness when the irradiation is stopped is not less than 300mcd / m². 2 The afterglow decayed to 0.32 mcd / m 2 The washing time shall not be less than 6 hours; after 50 washes according to AATCC61-2010 standard, the initial brightness retention rate of the fabric shall be ≥75%, and the color difference ΔE shall be ≤2 compared with that before washing, the light fastness shall be ≥4, and the rubbing fastness shall be ≥4; the ultraviolet protection factor UPF of the fabric shall be ≥50+, and the UVA transmittance shall be ≤5%.

2. The UV-resistant, colorfast fabric based on rare-earth aluminate long afterglow light conversion according to claim 1, characterized in that: The chemical composition of the rare earth aluminate long afterglow luminescent material particles is as follows: ,in The doping concentration is 0.5-5 mol%. The doping amount is 1-10 mol%.

3. The UV-resistant and colorfast fabric based on rare-earth aluminate long afterglow light conversion according to claim 1, characterized in that: The protective layer is a dense silicon dioxide layer with a thickness of 20-80 nm, and the silane coupling agent is γ-aminopropyltriethoxysilane or γ-methacryloyloxypropyltrimethoxysilane.

4. The UV-resistant and colorfast fabric based on rare-earth aluminate long afterglow light conversion according to claim 1, characterized in that: The ultraviolet light absorber is 2-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole, and the hindered amine light stabilizer is bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate.

5. The UV-resistant and colorfast fabric based on rare-earth aluminate long afterglow light conversion according to claim 1, characterized in that: The nano-anti-UV particles are rutile titanium dioxide with an average particle size of 20-50 nm, and their surface is modified by stearic acid or silane coupling agent.

6. The UV-resistant and colorfast fabric based on rare-earth aluminate long afterglow light conversion according to claim 1, characterized in that: The functional coating has a two-layer structure, including a base coating layer that is in direct contact with the base fabric layer and a top coating layer that covers the base coating layer. The base coating layer is a polyurethane resin layer containing a crosslinking agent with a thickness of 5-30 μm, which is used to improve the adhesion between the coating and the base fabric. The top coating layer is a light conversion functional layer with a thickness of 30-100 μm, which includes rare earth aluminate long afterglow luminescent material particles, ultraviolet light absorbers, hindered amine light stabilizers, binders, nano-anti-ultraviolet particles, crosslinking agents, dispersants and colorants.

7. The UV-resistant and colorfast fabric based on rare-earth aluminate long afterglow light conversion according to claim 6, characterized in that: The base coating also contains 1-5% nano-silica or nano-alumina by weight of the total base coating.

8. The UV-resistant, colorfast fabric based on rare-earth aluminate long afterglow light conversion according to claim 1, characterized in that: The base fabric layer is a blend of polyester fiber and cotton fiber with a blending ratio of 50:50 to 80:20, and the base fabric layer has undergone plasma pretreatment or alkali reduction treatment.

9. The UV-resistant and colorfast fabric based on rare-earth aluminate long afterglow light conversion according to claim 1, characterized in that: The colorant is a nano-pigment, which is encapsulated in polyacrylate microspheres by in-situ polymerization to form colored microcapsules with an average particle size of 0.5-5 μm.

10. The UV-resistant, colorfast fabric based on rare-earth aluminate long afterglow light conversion according to claim 1, characterized in that: The thickener is selected from at least one of polyurethane associative thickeners, acrylate copolymer thickeners, or sodium carboxymethyl cellulose, and the leveling agent is selected from at least one of polyether-modified polysiloxanes, polyacrylate leveling agents, or perfluoropolyethers.

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